Fuel consuming engines providing at least one, five, or ten horsepower are used to power all manner of aircraft, automobiles, boats and other passenger carrying vehicles, as well as many other devices, including non-passenger carrying vehicles and stationary devices such as generators. Numerous auxiliary DC power supplies are available for starting such engines, but since the power required for starting cannot typically be carried by a user, engines are frequently jump started using relatively long jumper cables for delivering power drawn from a power source. This is somewhat dangerous since damage to either or both vehicles can occur if the polarity is accidentally reversed, or if a spark ignites gas fumes. In addition, the second vehicle's battery must be positioned within the length of the jumper cables, which is often a problem if the disabled vehicle is tightly parked or otherwise difficult to access.
Additional problems exist where relatively long cables (i.e. cables greater than 5 feet in length) are used. For example, long cables can cause significant resistive energy losses due to the high current being transmitted, resulting in lower voltages at the engine starter, and adversely affecting starting performance. Long cables also tend to be heavy and cumbersome. Still further, long cables tend to have a relatively short lifespan due to exposure, frequent twisting, and or other stresses arising from use and storage.
Another problem that is sometimes encountered with jump starting existing vehicles is that the external auxiliary electrical contacts for receiving power may require specialized connectors, making it difficult to utilize general purpose battery packs as an external power source.
Thus there is a continuing need to develop new devices for providing auxiliary DC power for starting automobiles, boats, aircraft and other vehicles.